nanotube (IMAGE) University of California - Riverside Caption Plant viruses provide naturally occurring nanoparticles that are being repurposed for gene delivery into plant cells. Credit Nicole Steinmetz/UCSD Usage Restrictions none License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.